There is considerable variety among fertilizer products, in terms of their relative percentages of nitrogen (N), phosphorous (P), and potassium (K), the primary nutrients for plants. The percentages are expressed as a ratio and are prominently displayed as three numbers on the packaging of most brands. The numbers 5-10-5, mean that 5% of the product is nitrogen (N), 10% is available phosphate (P2O5), and 5% is soluble potash (K2O). The nitrogen may be further categorized as nitrates, ammoniacal and/or urea. The NPK ratio of a particular product is one way to judge whether it is a suitable fertilizer for a plant. General purpose fertilizers are typically balanced. They contain all three major nutrients—NPK—which are present in the proportions likely to be needed in a healthy soil. These general purpose fertilizers are suitable for use in plants where there are no special problems with the soil. They are most commonly and easily used in a granular form that can be spread uniformly with a mechanical spreader and watered in by rain or an irrigation system. In a greenhouse environment, liquid fertilizers, solid fertilizers diluted with water or solid fertilizers incorporated into the plant container itself are generally the preferred fertilizer application types.
Special purpose fertilizers are typically “unbalanced”, featuring a greater proportion of one or the other major nutrients, secondary nutrients such as calcium or magnesium, special micronutrients, or combinations there of, that may suit them for particular situations or plants. These products are marketed for specific uses. However, the marketing descriptions and materials may not always be horticulturally sound. For instance, there are fertilizers labeled for acid-loving plants such as azaleas and holly that help provide iron in a form that these plants can use. There are bulb fertilizers that provide generous amounts of phosphorus that bulbs require. Some are labeled specifically for lawns, tomatoes or trees. As a grower learns more about the plants and soil these special purpose products may be useful in maximizing his crop. However, a general purpose fertilizer is adequate in most situations.
Water soluble fertilizers are one genre of fertilizer products. Generally, water soluble fertilizers are fairly simple to make. The basic concept is to mix high quality raw materials in specific ratios that are advantageous to growing high quality plant material. Water soluble fertilizers are commonly used by non-agricultural professional growers (i.e. those that grow in artificial substrates and greenhouse mediums for sale to retailers) who rely primarily on nutrients from the water as opposed to the soil. These products are designed to be mixed with water in concentrated form, then diluted with injector systems that proportion the fertilizer solution to obtain the proper concentration. Therefore, in these circumstances, the selection of the proper fertilizer in terms of its relative percentages of nitrogen (N), phosphorous (P), potassium (K), calcium (Ca) and magnesium (Mg) is based on the water chemistry and in particular the water's alkalinity, calcium and magnesium levels. These types of fertilizers are used when a grower relies on nutrients from the water as well as the soil and therefore, uses information concerning water chemistry in conjunction with the selection of a fertilizer. Following traditional methods, a grower tests the water at his facility and then based on those test results, gets a fertilizer recommendation and application schedule based on the results of the water quality test and the specific crop being grown from a trained horticulturalist.
Because of the burden of the need to test the water and then consult a trained horticulturalist for recommendations, growers often choose to simply make a best guess on the selection of the proper fertilizer in terms of its relative percentages of nitrogen (N), phosphorous (P), and potassium (K) or the product name or how the product is marketed (e.g. the suggestion of how the product should be used). As a result, the present invention provides a novel system and method that facilitates appropriate fertilizer selection in an easy-to-use product selection system. Furthermore, this novel system and method helps to insure consistency in fertilizer recommendations.